Mark: Aware of the treasures of the intellect just before sleep, artists and intellectuals alike have found ways to tap into their theta state in manners both benign and dangerous. Not so long ago, people like Timothy Leary were touting hallucinogenic drugs as windows into the subconscious. On a healthier track, the artist Salvador Dali—he of the melting clocks and strangely shaped human figures—used to sit in a comfortable armchair holding a serving spoon in his hand. As he would begin to drift through the theta state toward sleep, the spoon would fall to the floor with a clang. Alarmed back to a wakeful state, Dali would immediately grab a pencil or brush and sketch the things he had just “seen” during his theta state.

Question: What does science, and in particular the study of different "brain waves" as tell us about the creative process?

Jess: Alpha waves do correspond to relaxed states, but they are usually observed with eyes closed. Mostly they correspond to the reduction of sensory input, as they appear immediately in most people upon closing the eyes with instructions to relax (8-12 Hz). Beta waves are higher frequency waves (> 12 Hz) and characterize active wakefullness, theta is between 4-8Hz and is still in the process of being understood.

It's a characteristic wave of REM sleep, and is not typically seen in healthy awake adults (except in the case of meditation! See Aftanas L, Golosheykin S (2005) Impact of regular meditation practice on EEG activity at rest and during evoked negative emotions. Int J Neurosci. 2005 Jun;115(6):893-909) - so we really could think of it, organizationally speaking, as a quiet, reflective, creative brain wave. But of course, it has a zillion other proposed roles as well, from sensori-motor integration, to short-term memory function, etc, etc. Delta waves are very slow (1-4Hz) and characterize the deepest stage of sleep (stages 3-4). So, what you learned wasn't entirely inaccurate, but it's not quite that simple, since all of these waves are seen in sleep except for beta.